Mucolipin-2 (TRPML2) non-selective plasma membrane cation channel (Ca2+ permeable). Shows inward rectification like TRPML1 and TRPML3 (Lev et al., 2010). Induces cell degeneration. Causes embryonic lethality, pigmentation defects and deafness, and regulates the acidification of early endosomes (Noben-Trauth, 2011). Found in the plasma membrane and early- and late-endosomes as well as lysosomes. Activated by a transient reduction of extracellular sodium followed by sodium
replenishment, by small chemicals related to sulfonamides, and by PI(3,5)P2, a rare phosphoinositide
that naturally accumulates in the membranes of endosomes and lysosomes, and thus could act as a
physiologically relevant agonist (García-Añoveros and Wiwatpanit 2014). TRPML2 can form heteromultimers with TRPML1 and
TRPML3; in B-lymphocytes, TRPML2 and TRPML1 may play redundant roles. TRPML2
may play a role in immune cell
development and inflammatory responses (Cuajungco et al. 2015).